RAID (Redundant Array of Inexpensive Disks or Redundant Array of Independent Disks) systems are in common use for securely and redundantly storing large amounts of data. The term RAID represents a family of techniques for managing collections of disks in such a way that desirable cost, availability, and performance properties are provided to host computing environments. RAID arrays come in various operating levels which are designated as RAID level 0 (RAID-0), RAID level 6 (RAID-6), etc. Additionally, there are multiple combinations of the various RAID levels that form hybrid RAID levels. Each RAID level represents a different form of data management and data storage within the RAID disk drive array. In conventional RAID systems and the like, the capacity of each disk in a given system generally has identical, or virtually identical storage capacity CJ such that C=C1=C2= . . . =CN for each of N storage systems. This makes distribution of storage among the various storage devices simple. While storage devices with capacity greater than C may be used in such a system, capacity over and above C is not used, resulting in an equivalent capacity that is limited to C. These disks are also normally very tightly coupled to a controller, and typically are contained within a single enclosure.
In home entertainment and other home network applications, as well as many business applications, storage devices tend to be added incrementally as storage needs grow. For example, a network including a television set top box, one or more home computers and a Personal Video recorder is generally established based on existing needs at the time of acquisition of each component, and often without regard for the data security provided in more advanced and secure storage systems such as RAID systems. In addition these systems are loosely coupled, over a network. In such systems, it is generally the case that C1≠C2≠ . . . ≠CN and it is not self evident from the operation of conventional RAID systems how one might distribute storage in order to assure secure storage in the face of an evolving network in a manner that assures no data loss if one component should fail. In fact, it is not evident how to proceed if any one of CJ≠CK in such a system. As a consequence, RAID technology and similar technologies are not widely used in such environments. Thus, conventional backup techniques (which are often not rigorously deployed and enforced) are generally used to protect data, if anything is done at all. This often results in large amounts of data going unprotected against accidental erasure or destruction or hardware or software failure.